Architecture-driven engineered lattice tetrahedral micro-scaffolds for extraskeletal osteogenesis.

While granular bone graft materials exhibit favorable surgical maneuverability, they still present critical drawbacks in clinical scenarios such as extraskeletal osteogenesis, including unstable osteogenic space maintenance and insufficient efficiency of blood supply and nutrient delivery. To address these bottlenecks, this study proposes an architecture-driven framework that transforms randomly distributed granules into engineered micro-scaffolds with programmable physical behaviors. Discrete element modeling showed that lattice tetrahedral structures enhance packing stability via geometric interlocking, while coupled computational fluid dynamics revealed architecture-dependent wetting and steady-state flow behavior. The DLP-fabricated bioactive glass micro-scaffolds exhibited printed porosities of 49.85-54.95%, permeability values of 4.29 × 10-10-1.35 × 10-9 m2, average wall shear stresses of 18.44-24.28 mPa under non-Newtonian flow, and mean BV/TV values of 9.05-12.74% at 12 weeks in a rabbit cranial vertical bone augmentation model. By decoupling macroscopic mechanical properties from microscopic hydrodynamic behaviors, this study establishes a biomechanics-based design paradigm for ordered granular micro-scaffolds, achieving synergistic integration of surgical adaptability and osteogenic predictability. This work offers theoretical support and technical pathways for developing high-performance bone graft alternatives.